Response of Commelina erecta L. to glyphosate formulations and role of starch and waxes in glyphosate sensitivity

PANIGO E.; CÉCCOLI, G; DELLAFERRERA I.M.; GARETTO, J; VEGETTI, A; PERRETA M.G.

ECOLOGÍA AUSTRAL

ASOCIACIÓN ARGENTINA DE ECOLOGÍA

Lugar: Buenos Aires; Año: 2022 vol. 32 p. 920 - 929

0327-5477

ABSTRACT. The aim of this study was to evaluate the effects of two formulations of glyphosate on adult plants and seedlings of Commelina erecta L and to determine whether stem starch storage and epicuticular waxes of leaves are involved in plant sensitivity to this herbicide. The formulations used were: isopropylamine salt (IPA) and diammonium salt (DA). All measured growth parameters and chlorophyll were negatively affected by both formulations. The IPA formulation showed a higher decrease in the branching rate and phyllochron, whereas the DA formulation showed a higher decrease in the elongation rate, chlorophyll content at 48 hours after application in adult plants, and the starch proportion in the stem basal section and caused more leaf injuries. All plants of C. erecta presented starch storage in the both stem section. After glyphosate application, stem starch proportion of the basal section evolved differently in both growth stages whereas stem starch proportion of the apical section showed an irregular variation. The amount of epicuticular waxes was higher in adult plants. These results show that both glyphosate formulations are ineffective for the management of C. erecta. The low sensitivity to glyphosate in C. erecta especially in plants higher than five leaves could be related to starch storage in stem and epicuticular waxes on leaves.